1. Field of the Invention
The present invention relates to a pure water tank for a fuel battery power generating system.
2. Description of Related Art
Pure water is indispensable to a fuel battery generating system in order to humidify fuel gas or oxidant gas supplied to stacks of fuel batteries. However, it should be noted that the pure water would freeze if a vehicle equipped with such a fuel battery generating system stops for a long period in a cold district.
Considering such a situation about the fuel battery generating system, Japanese Patent Application Laid-open No. 2000-149970 discloses one prior art structure where a pure water tank is provided with a spare tank around which a heater is wound. When starting the operation of the fuel battery generating system under the above-mentioned situation, the heater is energized to melt frozen water in the spare tank and subsequently, the resultant molten water in the spare tank is supplied for use.